Telegraph exchange system



Aug. 2l, 1934. F. s. KINKEAD Er AL TELEGRAPH EXCHANGE SYSTEM Filed June 25, 1931 2 Sheets-Sheet l F. S. KIN/(EAD /NVENTORS GJ DEL ATTORNEY Aug. 21, 1934. F. s. KINKEAD Er AL TELEGRAPH EXCHANGE SYSTEM Filed June 25. 1951 z'sheets-sneet 2 WhNAHm@ l 9W L11 R.

E5 K/NKEAD /Nl/fNTo/es n GJOZQNDEL n y ATTORNEY Patented Aug. 21, 1934 was v ff'rmsncfnnrn "Exoimnan 1 SYSTEM *assigner -ito implicitement-A25, 1931,;seriali1st).- Asiamo icecream.' (curro-am invention relatesttozprint'mgltelegraphsex- `cllangefsystems randfmore:particularlyftoi-thestaftionfcireuit for ruse: at asubScriiiers :printing :teliegralilfrstation. i tmf-objectief :thisfmventmnfis tofenaelefaimbescriber #at a printer lstation iin ,fa telegraph rexl'change f-sys`tem Ito communicate over `the visystem ima-'convenient anel-eiieient manner.

This-:invention"comprisesa'circuitrarrangement 310 .including i relay :an'dkeyfswitching meanstwhererbyfa#subsci'ilzier atY-theprinterfstation mayesignal an operator a fdistant #central cnice fffor 1' communiea'ticn over the telegraph Texchangemystern. "Means are 'proviiedvwherebm after communication ceases, "the subscriber nay Iindicate tto the central dii-lee operator that disconnection Ifram the transmissioncircuitfisrlesiretl. @'Circuitmeans :permit the 'starting L1anclfstolzaping. f tthe :printer set imotors from the distant kcentralrnice.` al

'20 buzzer llocated :at f' the 4fsuiascribefs 'rpremises :lis

utilized torattractthefattentionzof thesulaecr'iher Whenever r`a 'callingisubscrber is :connectedtotthe lcommunication `circuit.

FGne''feature of ilthis `invention iissu. :circuit `ar- 125 rangement whereby the :motors 'ifor fthe ssub# vsciberfspririter=set are controlledffromlthe cen- 'tralfofce over a 'pathf'traced?fromfonesideenfthe ioop-circuit to ground' this control rpath 'being transferred 'to 'a lcircuit local Ito lthe subscribers ls`tation as .soon as :the printer :set :ready communication. This feature "enablesfthe'switchboard operator "testant, J'transmitsignals tto,-'anii f. stop lthe printerfo'f -an unattended station.

iAnother feature A of this iinvention iis atthree- `535 position key, "forluse in initiating ra fcalltwhen throwninfone: position. andfor` disconnectingthe circuitwhen thrown: intheireversespcsition.

-A Tiuri-ther feature relates to :the means mployed for ='caus`ing 1a ilashing. recall :signal :zat

thesswl-tchboard.

:Referringltothefdrawings:

Fig. 111llustratesfschematicallya particulareembodiment .of :this invention :wherein a ssubscribens.staton :circuit :and .associated :line jack cir- A2155 cuit are 'Iadaptedffor metallicl'oopssignaling;

Fig. 2 iillustrates :schematically A'another' rembo'diment wherein sa :subscribers :station circuit andzassociated line jack circuit are sadaptedifnr grouniireturn operation; :and

50 zFiggillustrates .schematically acord circuitfat 555 ratusssshown Iconnectedtothefcentral cnice thy `lineo;xi'ntliiotors mand @Ra and terminating there- .at-ini1ineijaulssf6,f. :.Rrintereset -llis comprised essentiallyofzacontrol'relay adapted to start 'mi'dxstnp'the yimotor:driving-means Mfoi thelfset, a'ilmeirelayi'lfor recording-signal .impulses .and a() `tending .ccnntacts 'a .f1-serially connected vin the itip .side i'iI nf time iloop. ,'At "-.theestation `valso -is -a key which iused tino iinitiate a :call -Jcy .actuating tthelieey .toztlzcallinfg position and to f inform :the @zentral mince operator that disconnection (from *65 utile ommunication circuit is :desired foy factuatingtthe .key :to ..the irelease .pcsiticn. .-A buzzer uriiruiicator E8 `is 4frmployerl ato z'attractv the attenmf the Subscriber whenever tan `incoming wall isrcommetied l tozthei loop circuit.

llrhae pemtionrof fthe circuit'willmow helde- Assuming that the subscriber of Fig. 1 desires noiinitiate Fa @call-tto Lthe :central cnice, key 5 'will fbeamtuatedtto:.theileftaorzealling position. This v mtionvewill f clnse :a `:circuit to :light i lamp 9 ;in tthe Hx'aok fcineui-t at the :central rofliee #as fan :indi- 'catinn to the :operator that the `:subscriber defsires -a momrection :over :the exchange system.

iliisi'rcuit,isttmzcedifromznegativefl()volt bat- 80 teny-sll) vat :theucentral milice, through the upper rbredncontactsrnfsreiayill, one 'winding .of/diferentally wvolmdsslow release irelay '7, tip Tof the llonp, :contacts f3.4 rand linefrelay of fprinter'sset 11, :left 'i-lnwer :make :a contact l,of @key 1.15 85 rto e groundmnithe contact :and zarm-atureoffrelay '12,tthusxope1ating-thezrelay 7. ".Thefoperation ofrrelay'lfattthe central oiiice causes athemperfatiim rof'viaeiay -133 'from :ground con uthe =-armature `f-antlsmalce ccontacttof ,7 'Lto'.batter'y through =.the 90 4*winl'ling of irlay 13 :and inner break contact 'of rreiazyrl, inturn lighting ilampz over-an obvious circuit.

flhefcentralfoieecoperator, uponinoticingzlight- "eid lamp S9," will insert athe :answering iplug flue-of 95 thercortlccireuitiiigintol lineflack` associated wtthitheilightedilamp. flilre cordzcircuit emnloyed isf-faitypeiwell .fknown ini theaart; and :com- ,pisesmcircuithavmgiour polar relays 16, 17,

18 Aand 19 for repeating signal impulseszbetween 1er; line sectionsito 'which the @cord circuit :is ,conne'ctetl. ,:This .repeater circuitis f. disclosed =in .the y patentsztoilsM. Ee1l,i1,4'i9;4B0,.January 1, 1924 and F.5S.l1{kead,xl';'l52436, April :1, 1930, which are hereby :maderpart Lnot @this 1applicationas if 105 flyly includedzherein. y

The msertionmffqalug 1:4intofjack Gfwill oper-` atexhe "relay 11 in :the.=linejack. circuit: and'relay 1&5 iin :the rcord :circuit inver; la path @traced afrom hatterytthmughtthevwindingf.ofirelay:111,1sleeveof which will now be replaced by positive battery from the cord circuit. This lastgcircuit is-ftraced,

from T of the line, winding or relay '7, tip v,of jack 6, tip oi plug' 14, upper outerandinner-make; contacts of relay 15, upper windingjof,relay 20,1, break contacts of relay 21,'I'nakejcontvact of relay 18 (relay 18 operated when V relay/1.5 operated),

one winding each of relays` 16 and 11inormal break contact Vof the listening key to;. positive battery. The positive battery overthertip of plug 14 will operate relay -201 and keep'operated',

for the moment, relay 7. Relay 20, inaoperating;

will lock up on a circuit traced from positive battery on the lower outer make Contact of .relay '15, upper make Contact and winding of relay 20,

ring of plug 14, ring ofjack', inner make contact of relay 11, break contact of relay 22,- other winding ofV relay '7, ring side R off'the'loop circuit, winding 'or relay 23, right v-breakcontact of key 5, upper break contacts of relays 24.and`12,winding of control relay 2to ground, thus operating 'relays 2V-and 23.

Y Diierentially 1 wound, neutral relay 7 will remain operated .since-the currents through both of its windings are in v'such -direction as to aid in operating-therelay. .'Relay2, inoperating, will connect 110v volt-DC -power supply to the motor driving means M over an obvious circuit and will lalsor connect the DC Vsupply to Athe station 'apparatus'to condition the station circuit for proper operationat'this time.

A"The operation of slow release relay 23l causes the operation of relay 25Lon 'a zcircuittraced from ground on the armature and make-.contact of 23, through the winding of relay 25 to the ungrounded side of the DC supply on thev make contact of relay 2; Relay'ZS-isdesigned to be slow in releasing so Vas to hold up on printer signals. Relay 25, in operating, Ywill cause thezoperation of'relay 12, in turn, operating relay :24 and providing a locking circuit for control relay 2.. Relay 12 is operated'onza path-.from ground on the armature and make contact of relay 25. to the DC supply throughy the` winding of. ,relay 1-2 and make Contact of relay `2. "Relay 24 is oper-'- ated on a pathV from ground onthe 'ar-mature 'and make contact -ofrelay112 to the-DCsupply through the winding voi relay24 and themake contact or relay 2; "Relay 12,- in operating-,Tprovidesa path to locktup control relay 2 Vthrough the upper make contact of relay 12 and the' make contact ofi-'relay 2. .The operation'gof--relay@'24 closes T and Rot'- the lloop-through thegstation circuit and removes ground from-the-ring-side R.' It is tov be noted also, :that the operation of relay- 124removed ground from the tip side-T of the loop. The -loop` circuit-'ishow isolated K y i differentiallywound relay 7 will release'sinc'e positive battery -from the'cord circuit is applied to both of Vits-windings overa closed metallic loop. The release Aof'relay '7 will cause theope'ration VVoi"l relay22 ona pathfrom groundon the'armature and .breakcontact ofi '7,-' upperjwindin'gof relay 22,V ring-:off jack G'and plug 14, winding'and coritacts' of relay 20, :to positive battery on'the Vlower outer make con-. tact'of relay l5, thus keeping operated `the relay A t this time,

20. The operation of-relay 22 will transfer the ring side R of -the loop from positive battery over the ring of, the cordcircuit to negative 130 volt battery 10f`in the line jack circuit. This circuit is traced from R of the loop, one winding of relay 7, make contact and lower winding of relay 22, lower inner make contact of relay 11 to'negative battery 10. It is to be noted that the circuit is no w closed from negative battery 10 over R of the loop through the station ap- ;paratus, back over Tof the loop, to positive battery in Ythe cord circuit. Current is now flowing through each ofthe two windings of difieren- A'tially wound relay 7 in such directions as to `oppose each other and to prevent the operation lof, Vrelay-'1-A which-continues to stay released.

The operator at the central ofice may now communicate with the subscriber by actuating the listening key in the cord circuit and typing on the keyboard of her printer set. The actuation of. `the listening-key `will connectthe operatorisprinter in series with'the -tip side ofthe line and. Ywill, replace the batteryon the listen.- ing key. Upon receiving the code number of the subscriber with whom the calling-party wishes to communicate, Ithe operator-will insert calling plug 27 or the cord circuitinto -jack-. ofthe called subscribers line. This action will cause ithe -operation of relay 28 in; the cord lcircuit and relay' 11 .in the line jack-circuit of the; called subscriber, in av manner-similar tothathereto- .fore described in connection with the operation Aer1-relay l5 and relay :llin the line jack-circuit of .thecalling `subscribers circuit. Positive-bat- .tery vwill Vbe' connected over the ringside- R- -of the loop to operate relay 22, on a pathfrom positive-batteryl on the-upper make contacts of the listening key in kthe' 'cord circuit, lower middle make contactsfof relay 28, ring of plug 2'7,A ring of jack 6,-;upperwinding -oi relay 22 to ground on the armature and break contact of relay 7. Disconnectlamp A31 will light'up on a path Vfrom battery on the lower outer make contacts of relay 28, break contacts of relay 29 .to ground -through the lamp. v.The-operation of relay.-22 will connect. R- of the loop through -thelower windingy of relay 22 `to negative batteryl() on the inner makecontact of relay 11. This negative battery onv the .ring R of the loop will cause the operation of relay 23 and relay 2 in the rcalled subscribersstation lcircuit onia path -from-Rof theloop,- winding of relay 23, right break contact of .key-5, upper break contacts` of relays 24 and 12 winding of 'control relay 2 tol ground. lhe..operationl of relay 2 will connectj the power supply to-the motor driving means M and tothe stationapparatus. Relay'23, in operating,m w,ill operate. relay 25 over a circuit hereinbefore Adescribed. '.Relay 25, in operating, willactuate buzzer 8 to attract the subscribers, attention, `on a circuit traced from groundon the left inner break contact of key 5, lower make Contact of relay 25, buzzer 8 to the rDC supply. Relay` 25, inoperating, also causes the operation of relay 12, in

turn; operating-,relay 24.. This has been def scribed-'.hereinbefore.- Relay 2 will lock up through-its own 'contacts and those of relay 12.'

The tiprside T of the loop will nowbe closed y through the station apparatus to the ring side R oi-if the loop. Buzzer 8 lwill `continue to buzz until the subscriberfactuates key.5 to the calling position which will remove the ground on 'key 5 from buzzer 8. gThe closure of T and R through the.r station apparatus will cause the operation of relay-29 in the cord circuit von a circuit traced -frorn negative tbatter-yiloverlRcofthe icophack '.overiTioi Ethelloop, itip ci .fjack i6, itin @fremd 5.27, runner router fan'd armer make contactsrof'rrelay 228,1uppenwndingfof :relay :.29,`.break :contacts of Is, lrelay ;3'0,nnake:contactsl .of :relay llfonewwinding :each dif relays .18 I"and :1.9 .to :positive abattery. LR'eIayLQQ, :in :operatingl will extinguish lamp 31 andlockzup .over .itszcontacts :lowerfwindingf-and Y iring sidentthe:cordltoigroundtthroughpthefwindun -ing fo'f :relay .22 .and back fcontac-ts Ifof frelayv7. Dilerentialrelay rIrwill be 'unoperatedzat this itinre :due to vthe .opposing current #through :its -windings.

If :the :called :subscriber ,rdoes fnot eanswer, ithe operator nr the calling V.subscriber #may wtransmit to the printer set 1 of theicalled partyaon antun- .fattended ibasis, ithe .'Istation circuit sof Vithe .called Subscriber inow i being iin condition for :the irecep- :tion ofisignaling impulses. iRelayrZB ;is: designed tobe sl'ow .1in :releasing andiwill remain operated duringtlie transmissionidf impulsessofastopre- '.ve'ntv the `station circuit from ...returning to inormal WhileLsignalsriare fleeing itransmittedfrom fthe lfswitchboarolonanfunattended fbaslsg Y To-give -`the .disconnect fsignal, ..the subscriber actuates key 5 from'theileft:ornallingrpositionito the right or release position momentarily, and thenirestores the key Lto :norm-a1. The actuation of key:5 ttofthe.releaseipnsition will open the R side of the loop and place ground on the T side of the loop, thus causing the release of relay 23. The release of relay 23 will release relay 25, in turn, opening up the operating path of relay 12 which will also release and cause the release of relays 24 and 2. The return to normal of control relay 2 stops the operation of the motor driving means M. The opening of the ring side R of the loop will also cause the release of relay 22 in the line jack circuit. The tip T of the loop is grounded by the operation of key 5 tothe release position on a circuit traced from ground through the lower outer right make contact of key 5, Winding of printer line relay 3 and sending contacts 4 of printer set 1, T of the loop,v one winding of relay '7 to battery over the tip of the cord circuit, op-

eratng the relay '7. Differential relay '7 operates at this time since current is now owing in only one of its windings. It is to be noted that relay 20 in the cord circuit does not release at this time *mi since it is kept operated by current ilowing through its upper winding over the tip side of the cord. Relay 20 will stay operated until key 5 is returned to normal, at which time, ground is removed from the tip T of the loop.

The release of relay 20 will light the disconnect lamp 26 in the cord circuit as an indication to the operator that the subscriber wishes to be disconnected from the system. The release of relay 20 also causes the operation of relay 21. The lamp `I circuit for lighting lamp 26 is traced from battery on the lower outer make contact of relay 15, break contact of relay 20 to ground through lamp 26. Relay 21 is operated from the same battery on the break contact of relay 20 which lights the lamp.

The actuation of key 5 to normal Will remove ground from T of the line and cause the release of relay '7.

Relay '7 is designed to be slow in releasing to insure that relay 20 in the'cord circuit has completely released before the armature of relay '7 is restored to its normal position. Otherwise, relay 20 may remain operated from the ground on the armature and break contact of '7 over the ring side of the cord. Although the disconnect feature has been described only in connection with the-:answering 1plug,iit`fshould.be' understood what itheinircuttsassociatedwiththe callingiplugifunc- -tionzinfan identi'calimanner. 1 lltiisfo'tten. desirable ztofattract the: attentionro'f the aoperator"fat=the vcentral .fiice awhile `@the 'subfscrlberisstillfconnectedto vaf'communicationl cir- `c'uiftfover tltefexchange'system. fIh-is mayrbefajcfcomplishedibm-alternately actuatingkey 5"to the rveallingfarrdlrelease positions. "When thisis done the fdiseonneotilarnpfin lthe cord circuit will 'be li-tl'luring theitime the keyisin'fits normal position -fafteribeing :actuated1 to 'the Vrelease position. llheiaetuationi df'koyto its calling position` while athercordvcircuitis connectedto jack '6 will cause the .ireoperation fof 'fthe' rela-'ys '5in- "the subscriberls stationi circuit inf'"a`1n'ianne'r;s'imilar lto thathereribforedescribedin-fconnection -with'initiating a Fig C2 iillustrates fa -subscriber-s @station "circuit fandiwassoc'iated lline -jackcircuit avialtefd"fior grcuniifreturnoperation. "Toiinitiatera-callkey5 is actuated to the calling position. This action Willrpl'ace-groundi oni-thetipv sidefIo`f ithe loop to operatefr'layiiBTZin'tlre'line jack circuit onfapath K traced Ffrom lbattery von the inner break 1 Contact im!) 'of ireiay P33, Kwinlzling fof A#rela/y 32,171' of the lloop, 'asendingfcontacts 4and`lwindingoflinerelay 3 'o'f lthefsubscrberis printer lset, loWer 'l'e'ft 7makeA con# tracts-of =keyt`5i-to`l ground. l@Relay 32 in fop'eratin-g will light up lamp 9 over an obvious circuit.

The central ofce operator, upon noticing the lighted lamp, will insert plug 14 of the cord circuit into one of the jacks 6 associated with the lighted lamp. This action will cause the opera- Y tion of relay 33 in the line jack circuit and relay 13m 15 in the cord circuit on a path from battery through the winding of relay 33, sleeve of jack 6, sleeve of plug 14, winding of relay 15 to ground. i The operation of relay 33 will extinguish lamp 9 and remove battery 34 from the tip side T of the H5 loop. This battery, however, is replaced bypositive battery in the cord circuit over the tip of the plug 14. The circuit traced by the battery over the tip of the plug is identical with that hereinbefore described in connection with the operation of the circuit illustrated in Fig. 1. Relay 20 will operate over this circuit.

The insertion of plug 14 in jack 6 also causes the operation of relays 2 and 35 in the station circuit over a circuit traced from positive battery on the lower outer make contact of relay 15, make contact and one Winding of relay 20, ring of plug 14, ring of jack 6, R of the loop, right break contact of key 5, windings of relays 35 and 2, in series, to ground. Relay20 will lock up overrthis circuit. Control relay 2, in operating, Will condition the printer set for operation. Communication may now take place over the tip T of the loop on a circuit from positive battery in the cord circuit to ground in the station ciri395 cuit. Relay 3 will follow all signals.

A recall signal from thesubscribers set is given by operating key 5 alternately to the calling and release positions. Each time the key is actuated to the release position, the tip and ring 3546 sides of the loop are opened, causing relay 20 in the cord circuit to release and lamp 26 to light, and each time the key is actuated to the call position, the tip and ring. sides of the loop are closed through to ground at the station, causing relay 20 to operate and lamp 26 to be eX- tinguished.

A call may be received from the central oiiice by the insertion of plug 27 into jack 6. This action will operate relays 28 and 33 over the sleeve is@ rio circuit. Relays 2 andy 35 ofthe station circuit will operate over the ringof the' Aloop -from positive battery on the uppermake. contacts ofthe listening key in the cord circuitlower middle make contacts of relay 28, ring of plug 27 and jack 6, R of theloop, right break contactsof key `5 to groundthrough the winding of relays 35 and 2. The operation of relay 35 will causethe operation of buzzer 8 over an obvious circuit; to attractthe attentionpf the subscriber. Itshould be noted, also, that the operation of relay 35 connected ground from its lower Contact to the tip 'Il of the loop through line relay 3 and sending contacts 4 nation, a printer set', a. motorfdriving means for said set, circuit means at said printer set, a threepositionswitching memberlocated at said printer s et, aswitchboard,l a normally deenergizedloop circuit extending from s aid circuit means to said f f switchboard, a plurality-of signal indicating means `at said switchboard, fone 'of which ar- .ranged'tooperate when said switching-member is actuated to one of its operated positions, anda link'circuit at said switchboard arranged to .be

connected'to said loop circuit when said indicat- 1 ing lmeans operates whereby said loop circuitis energized andsaid circuit means is operatedfor .starting saidl motor driving means, said circuit .means being responsive tothe actuation' of said switching meansto another of its operated positions for stopping said motor driving means.

2. In a .telegraph exchange system according to claim 1, wherein the other of said signalindicating meansis arranged to operate when said switching member is actuated to the secondmentioned operated position '3; `In combination in a subscribers'stationl circuit, .a printer, motor driving means for said printer, a 'transmission line, a relay serially con*- nected in said line land adapted when operated bycurrent over said line to actuate saidA motor driving means, and circuit meansV for maintaining 'the actuation of said motorl driving means, said relay being adapted to lock up over said circuit 'meansg' and means for releasing said relay to stop said-motor driving means.

vFULLERTON s. KINKVEAD. 'z

GEORGE J. KNANDEL. 

